39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.Ar...39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.展开更多
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con...Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.展开更多
Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between...Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between adjacent filled drifts,which can weaken the integrity of the backfill roof.These interfaces also lead to two common drift layouts:aligned drifts and staggered drifts.However,less attention has been paid to the interfaces and the two drift layouts were not adequately distinguished in previous studies.In this paper,the interfaces between filled drifts were firstly considered to investigate the stability of backfill roof.Failure modes and strength requirements of backfill roof in aligned and staggered drifts are comprehensively investigated by FLAC3D,with a focus on considerations of varied shear parameters of the interfaces.Results show that failure modes in aligned drifts transition from block sliding to top caving,bottom caving or sloughing as the interface cohesion increases from zero to at least half of the backfill cohesion.Further increases in interface cohesion allow aligned drifts to behave as if there are no interfaces between them.The critical stability conditions of backfill roof in aligned drifts were mostly determined by the interface strength instead of the backfill strength.However,the stability of backfill roof in staggered drifts is barely affected by the interface strength.The outcomes are expected to provide references for mining engineers to optimize drift layouts and perform cost-effective backfill roof strength design at mines using underhand drift-and-fill mining method.展开更多
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral...Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.展开更多
Deep Underground Science and Engineering(DUSE)is pleased to present this special issue on Groundwater and Stability in Deep Mining.As mining operations progress to greater depths to meet the growing global demand for ...Deep Underground Science and Engineering(DUSE)is pleased to present this special issue on Groundwater and Stability in Deep Mining.As mining operations progress to greater depths to meet the growing global demand for mineral resources and energy,the challenges associated with groundwater control and rock mass stability have grown increasingly critical.These challenges are exacerbated by complex geological conditions,structural heterogeneity,and intense mining-induced disturbances.This special issue seeks to address these challenges by showcasing cutting-edge research and technological advancements in the field.展开更多
Deep-sea mining has emerged as a critical solution to address global resource shortages;however,the mechanical interaction between tracked mining vehicles(TMVs)and soft seabed sediments presents fundamental engineerin...Deep-sea mining has emerged as a critical solution to address global resource shortages;however,the mechanical interaction between tracked mining vehicles(TMVs)and soft seabed sediments presents fundamental engineering challenges.This study establishes a multiscale modelling framework coupling the discrete element method(DEM)with multi-body dynamics(MBD)to investigate track-seabed dynamic interactions across three operational modes:flat terrain,slope climbing,and ditch surmounting.The simulation framework,validated against laboratory experiments,systematically evaluates the influence of grouser geometry(involute,triangular,and pin-type)and traveling speed(0.2–1.0 m/s)on traction performance,slip rate,and ground pressure distribution.Results reveal rate-dependent traction mechanisms governed by soil microstructural responses:higher speeds enhance peak traction but exacerbate slip instability on complex terrain.Critical operational thresholds are established—0.7 m/s for flat terrain,≤0.5 m/s for slopes and ditches—with distinct grouser optimization strategies:involute grousers achieve 35%–40%slip reduction on slopes through progressive soil engagement,while triangular grousers provide optimal impact resistance during ditch crossing with 30%–35%performance improvement.These findings provide quantitative design criteria and operational guidelines for optimizing TMV structural parameters and control strategies,offering a robust theoretical foundation for enhancing the performance,safety,and reliability of deep-sea mining equipment in complex submarine environments.展开更多
Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection ...Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection guideline of this method was also described. While comparing the parameters of caving mining with equivalent height, the subsidence efficient can be calculated according to the mining height and bulk factor of sagging zone and fracture zone, the tangent of main influence angle of solid backfilling mining is reduced by 0.2-0.5（while it cannot be less than 1.0）. For sake of safety, offset of the inflection point is set to zero, and other parameters, such as horizontal movement coefficient and main propagation angle are equal to the corresponding parameters of caving mining with equivalent height. In the last part, a case study of solid backfilling mining subsidence prediction was described. The results show the applicability of this method and the difference of the maximum subsidence point between the prediction and the observation is less than 5%.展开更多
Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method ...Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps展开更多
Shear strain energy is a pivotal physical quantity in the occurrence of earthquakes and rockbursts during deep mining operations.This research is focused on understanding the changes in shear strain energy in the cont...Shear strain energy is a pivotal physical quantity in the occurrence of earthquakes and rockbursts during deep mining operations.This research is focused on understanding the changes in shear strain energy in the context of retreating longwall mining,which is essential for the optimized design and mitigation of rockbursts and seismic events.Through the application of innovative analytical models,this study expands its analytical range to include the variations in shear strain energy caused by fault coseismic slip.An integrated methodology is utilized,taking into account the changes in coseismic and fault friction parameters as well as enhancements in mining-induced stress and existing background stresses.Our numerical investigation highlights the significance of mining location and fault characteristics as key determinants of shear strain energy modifications.The analysis demonstrates significant spatial variability in shear strain energy,especially noting that fault slip near the mining face greatly increases the likelihood of rockburst.This finding emphasizes the need to integrate fault coseismic slip dynamics into the triggering factors of rock(coal)bursts,thus broadening the theoretical foundation for addressing geological hazards in deep mining operations.The results are further corroborated by observational data from the vicinity of the F16 fault zone,introducing the concept of mining-induced fault coseismic slip as an essential element in the theoretical framework for understanding rockburst triggers.展开更多
Using electric motors instead of diesel engines as the driving system for mining excavators can reduce the energy consumption and operating costs.However,pure electric-driven mining excavators are prone to unexpected ...Using electric motors instead of diesel engines as the driving system for mining excavators can reduce the energy consumption and operating costs.However,pure electric-driven mining excavators are prone to unexpected power outages in mines because of drastic changes in load power,leading to significant fluctuations in the power demand of the grid,which in turn affects production.To solve the above problem,a pure electric-driven mining hydraulic excavator based on electric-motor-driven swing platform and hydraulic pumps was used as the research object.Moreover,supercapacitors and DC/DC converter,as the energy storage system(ESS)adjust the output power of the grid and recover the braking kinetic energy of the swing platform.Subsequently,a novel integrated energy management strategy for a DC bus voltage predictive controller based on the power feedforward of fuzzy rules is proposed to run mining excavators efficiently and reliably.Specifically,the working modes of the ESS are determined by the DC bus voltage and state of charge(SOC)of the supercapacitor.Next,the output power of the supercapacitor and the DC bus voltage were controlled by adjusting the charging and discharging currents of the DC/DC converter using a predictive controller and fuzzy rules.In addition,a digital prototype of the excavator was verified using an original machine test.The performance of the different strategies and driven systems were analyzed using digital prototypes.The results showed that,compared with traditional excavators with diesel engines,the operational cost of the developed excavators was reduced by 54.02%.Compared to pure electric-driven excavators without an ESS,the peak power of the grid for the developed excavators was reduced by 10%.This study designed an integrated energy management strategy for a pure electric mining excavator that can regulate the power output of the grid and maintain the stability of the bus voltage and SOC of the ESS.展开更多
Salt deposits in China predominantly originate from lake deposits,characterized by thin salt beds interspersed with numerous interlayers,collectively termed bedded salt formations.Historically,the solution mining prac...Salt deposits in China predominantly originate from lake deposits,characterized by thin salt beds interspersed with numerous interlayers,collectively termed bedded salt formations.Historically,the solution mining practices have adopted the layered solution mining approach,inspired by coal mining techniques.However,this approach fails to account for the unique challenges of salt solution mining.Practical implementation is inefficient,costs escalate post-construction,and cavern geometry is constrained by salt beds thickness.Additionally,resource loss in abandoned beds and stability risks in adjacent mining zones remain unresolved.This study investigates mining scheme selection for low-grade salt deposits in Huai'an Salt Basin,introducing a continuous solution mining method that traverses multiple interlayers.Through comprehensive analysis of plastic deformation in caverns and surrounding rock,volume shrinkage rates,and economic costs comparing continuous and layered solution mining approaches,the results demonstrate that:(1)In the layered solution mining with horizontal interconnected wells scheme,plastic deformation zones propagate unevenly,posing interlayer connectivity risks.Concurrently,roof subsidence and floor heave destabilize the structure;(2)the continuous solution mining with horizontal interconnected wells scheme reduces plastic deformation zones to 3.4%of cavern volume,with volumetric shrinkage below 17%,markedly improving stability;(3)Economically,the continuous solution mining scheme generates caverns 2.43 times larger than the layered solution mining,slashing unit volume costs to 41.1%while enhancing resource recovery and long-term viability.The continuous method demonstrates distinct economic advantages and achieves higher resource utilization efficiency in solution mining compared to layered mining.Furthermore,its superior cavern stability presents strong potential for large-scale implementation.展开更多
To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and ...To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and Ni in China’s Dexing copper mining district through paired sampling of water-amphibians,soil-earthworms,and air-lichens.Advanced methodologies were employed,including ICP-MS quantification for heavy metals,geochemical indices(Igeo,BCF,BAF)to assess bioavailability,NMDS for source apportionment,and HPLC to detect DNA methylation alterations.Aquatic systems exhibited severe Cd/Pb enrichment(16.25-24.42μg/L;11-15×WHO limits),while agricultural soils showed extreme Cd contamination(1.5 mg/kg;15×background).Biota displayed metal-specific accumulation:frogs achieved BCFs>1,000 for Pb/Cd,earthworms showed pH-modulated BAFs>2.5 for Cd/As,and lichens recorded 100-1,000×atmospheric Cr enrichment.NMDS resolved three contamination pathways:mining-derived Cd/Pb/As(MDS1=2.56),atmospheric Cr(PC2=1.84),and geogenic Ni.Cd dominated ecological risks(Eri=554.25;RI 300),while atmospheric Cr drove carcinogenic risks(TCR=4.11×10^(-5))exceeding safety thresholds.The source-media-biota-risk framework pioneers the integration of geochemical transport with epigenetic toxicity biomarkers,demonstrating that sub-lethal Cd/Pb exposure induces genome-wide DNA hypomethylation(2.4%-6.6%reduction;ρ=−0.71 to−0.91).This paradigm shift prioritizes bioavailability-informed regulations over concentration-based metrics,offering actionable strategies for sustainable development goals-aligned mining pollution control.展开更多
With the third innovation in science and technology worldwide, China has also experienced thismarvelous progress. Concerning the longwall mining in China, the ＂masonry beam theory＂ （MBT） wasfirst proposed in the 1...With the third innovation in science and technology worldwide, China has also experienced thismarvelous progress. Concerning the longwall mining in China, the ＂masonry beam theory＂ （MBT） wasfirst proposed in the 1960s, illustrating that the transmission and equilibrium method of overburdenpressure using reserved coal pillar in mined-out areas can be realized. This forms the so-called ＂121mining method＂, which lays a solid foundation for development of mining science and technology inChina. The ＂transfer rock beam theory＂ （TRBT） proposed in the 1980s gives a further understanding forthe transmission path of stope overburden pressure and pressure distribution in high-stress areas. In thisregard, the advanced 121 mining method was proposed with smaller coal pillar for excavation design,making significant contributions to improvement of the coal recovery rate in that era. In the 21st century,the traditional mining technologies faced great challenges and, under the theoretical developmentspioneered by Profs. Minggao Qian and Zhenqi Song, the ＂cutting cantilever beam theory＂ （CCBT） wasproposed in 2008. After that the 110 mining method is formulated subsequently, namely one stope face,after the first mining cycle, needs one advanced gateway excavation, while the other one is automaticallyformed during the last mining cycle without coal pillars left in the mining area. This method can beimplemented using the CCBT by incorporating the key technologies, including the directional presplittingroof cutting, constant resistance and large deformation （CRLD） bolt/anchor supporting systemwith negative Poisson＇s ratio （NPR） effect material, and remote real-time monitoring technology. TheCCBT and 110 mining method will provide the theoretical and technical basis for the development ofmining industry in China.展开更多
In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining （NM）, top-coal caving mining （TCM） and protective coal-seam mining （...In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining （NM）, top-coal caving mining （TCM） and protective coal-seam mining （PCM）, are modeled using discrete element software UDEC, The numerical results show that different mining layouts can lead to different mining-induced stress fields, resulting in diverse fracture fields, For the PCM, the mining influenced area in front of the mining faces is the largest, and the stress concentration factor in front of the mining faces is the lowest, The spatial shapes of the mining-induced fracture fields under NM, TCM and PCM differ, and they are characterized by trapezoidal, triangular and tower shapes, respectively, The fractal dimensions of mining-induced fractures of the three mining layouts decrease in the order of PCM, TCM and NM, It is also shown that the PCM can result in a better gas control effect in coal mines with high outburst potential, The numerical results are expected to provide a basis for understanding of mining-induced gas seepage fields and provide a reference for high- efficiency coal mining,展开更多
1.Introduction Changes in land use are key factors promoting global climate change,and the side effects of mining activity that destroy the soil,vegetation,and biodiversity lead to imbalanced carbon cycling in terrest...1.Introduction Changes in land use are key factors promoting global climate change,and the side effects of mining activity that destroy the soil,vegetation,and biodiversity lead to imbalanced carbon cycling in terrestrial ecosystems.展开更多
The rehabilitation of coal mines is an up-to-date issue, heavily discussed not only by the industry but also by scientists and the adjacent communities since open cut coal mining has extensive impacts affecting all pa...The rehabilitation of coal mines is an up-to-date issue, heavily discussed not only by the industry but also by scientists and the adjacent communities since open cut coal mining has extensive impacts affecting all parties. Whereas, before and during the mining process not only nature but sometimes also the population of a whole region has to give way to a mine, the consequences of the operations remain long after mining closure. Typically a once intact and functioning ecosystem is replaced with a destroyed wideness evocative of a moon landscape. Fortunately, the awareness of the need to rehabilitate the destroyed nature is increasing steadily and all involved parties are making efforts to improve the situation, even if it is a major challenge to bring all parties to a consensus. Therefore, a legislative basis is required and the know-how of optimal rehabilitation solutions must be developed. In this article the rehabilitation of mined land in Australia and Germany are compared. More precisely the article will present an overview of the legislative regulations, certain applied methods of rehabilitation work and the problems that are likely to occur in respect to the influence of mining on nature.展开更多
Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts...Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.展开更多
The complex and diverse nature of coal mining sites,including different landforms and working conditions,presents challenges for rehabilitation efforts.To address this,we conducted a comprehensive experimental study f...The complex and diverse nature of coal mining sites,including different landforms and working conditions,presents challenges for rehabilitation efforts.To address this,we conducted a comprehensive experimental study focusing on microbially induced calcium carbonate precipitation(MICP)remediation,considering the fracture characteristics of coal mining sites.The MICP-restored samples were subjected to confined/unconfined compressive strength,uniaxial/triaxial permeability,and souring tests to assess their restoration efficacy.The results showed that under similar mining conditions,the average depth of parallel fractures was 0.185 m for loess ridges,0.16 m for the valley,and 0.146 m for the blown-sand region,while the average depth for boundary fractures was 0.411 m for loess ridges,0.178 m for the valley,and 0.268 m for the blown-sand region.Notably,parallel fractures showed negligible filling in all landforms,whereas boundary fractures in the blown-sand region were completely filled with wind-deposited sand.The valley landform was filled with alluvium and wind-deposited sand,whereas the loess landform was filled with wind-deposited sand and loess.MICP-restored soil samples in all landforms achieved a strength comparable to remolded fracture-free soil samples.Across all landforms,the maximum permeability coefficient of MICP-restored soil samples closely matched that of remolded fracture-free soil samples.Under similar topographic and rainfall conditions MICP restorations scoured 31.3 g on blown-sand region,19.3 g on loess ridges,and 17.6 g on valleys.These research findings provide an experimental foundation for MICP repair of coal mining ground fractures.展开更多
Belt conveyors are extensively utilized in mining and power industries.In a typical coal mine conveyor system,coal is transported over distances exceeding 2 km,involving more than 20000 idlers,which far exceeds a reas...Belt conveyors are extensively utilized in mining and power industries.In a typical coal mine conveyor system,coal is transported over distances exceeding 2 km,involving more than 20000 idlers,which far exceeds a reasonable manual inspection capacity.Given that idlers typically have a lifespan of 1-2 years,there is an urgent need for a rapid,cost-effective,and intelligent safety monitoring system.However,current embedded systems face prohibitive replacement costs,while conventional monitoring technologies suffer from inefficiency at low rotational speeds and lack systematic structural optimization frameworks for diverse idler types and parameters.To address these challenges,this paper introduces an integrated,on-site detachable self-powered idler condition monitoring system(ICMS).This system combines energy harvesting based on the magnetic modulation technology with wireless condition monitoring capabilities.Specifically,it develops a data-driven model integrating convolutional neural networks(CNNs) with genetic algorithms(GAs).The conventional testing results show that the data-driven model not only significantly accelerates the parameter response time,but also achieves a prediction accuracy of 92.95%.The in-situ experiments conducted in coal mines demonstrate the system's reliability and monitoring functionality under both no-load and fullload conditions.This research provides an innovative self-powered condition monitoring solution and develops an efficient data-driven model,offering feasible online monitoring approaches for smart mine construction.展开更多
A deep-sea mining riser is a crucial component of the system used to lift seafloor mineral resources to the vessel.It is prone to damage and failure because of harsh environmental conditions and internal fluid erosion...A deep-sea mining riser is a crucial component of the system used to lift seafloor mineral resources to the vessel.It is prone to damage and failure because of harsh environmental conditions and internal fluid erosion.Furthermore,damage can impact the response characteristics of the riser,but varying environmental loadings easily mask it.Thus,distin-guishing between riser damage and environmental effects poses a considerable challenge.To address this issue,a cantilevered model is created for a deep-sea mining riser via the concentrated mass method,and a time-domain analytical strategy is developed.The vortex-induced vibration(VIV)response characteristics of the riser are initially examined,considering various damage conditions and flow velocities.The study results revealed four primary observations:(a)effective tension can serve as a reliable indicator for identifying damage at lower velocities;(b)there are noticeable differences in displacement between the healthy and damaged risers in the in-line direction rather than the cross-flow direction;(c)frequency characteristics can more effectively distinguish the damage conditions at high flow velocities,with the mean square frequency and frequency variance being more effective than the centroid frequency and root variance frequency;(d)displacement differences are more sensitive to damage occurring near the top and bottom of the riser,while both velocity variations and structural damage can influence displacements,especially in regions between modal nodes.The vibrational behavior and damage indicators are clarified for structural health monitoring of deep-sea mining risers during lifting operations.展开更多
文摘39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.
文摘Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.
基金supported by Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(Grant No.2024ZD1003705)the Beijing Nova Program(Grant No.20220484057)support from China Scholarship Council under Grant CSC No.202110300001.
文摘Stability of base-exposed backfill roof in underhand drift-and-fill mining is crucial for the safety of those working beneath.Given the commonly used primary-and-secondary mining sequence,interfaces are formed between adjacent filled drifts,which can weaken the integrity of the backfill roof.These interfaces also lead to two common drift layouts:aligned drifts and staggered drifts.However,less attention has been paid to the interfaces and the two drift layouts were not adequately distinguished in previous studies.In this paper,the interfaces between filled drifts were firstly considered to investigate the stability of backfill roof.Failure modes and strength requirements of backfill roof in aligned and staggered drifts are comprehensively investigated by FLAC3D,with a focus on considerations of varied shear parameters of the interfaces.Results show that failure modes in aligned drifts transition from block sliding to top caving,bottom caving or sloughing as the interface cohesion increases from zero to at least half of the backfill cohesion.Further increases in interface cohesion allow aligned drifts to behave as if there are no interfaces between them.The critical stability conditions of backfill roof in aligned drifts were mostly determined by the interface strength instead of the backfill strength.However,the stability of backfill roof in staggered drifts is barely affected by the interface strength.The outcomes are expected to provide references for mining engineers to optimize drift layouts and perform cost-effective backfill roof strength design at mines using underhand drift-and-fill mining method.
基金funded by geological survey project of China Geological Survey(DD20211404)。
文摘Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.
文摘Deep Underground Science and Engineering(DUSE)is pleased to present this special issue on Groundwater and Stability in Deep Mining.As mining operations progress to greater depths to meet the growing global demand for mineral resources and energy,the challenges associated with groundwater control and rock mass stability have grown increasingly critical.These challenges are exacerbated by complex geological conditions,structural heterogeneity,and intense mining-induced disturbances.This special issue seeks to address these challenges by showcasing cutting-edge research and technological advancements in the field.
基金financially supported by the National Key Research and Development Program of China-Young Scientist Project(No.2024YFC2815400)the National Natural Science Foundation of China(No.52588202).
文摘Deep-sea mining has emerged as a critical solution to address global resource shortages;however,the mechanical interaction between tracked mining vehicles(TMVs)and soft seabed sediments presents fundamental engineering challenges.This study establishes a multiscale modelling framework coupling the discrete element method(DEM)with multi-body dynamics(MBD)to investigate track-seabed dynamic interactions across three operational modes:flat terrain,slope climbing,and ditch surmounting.The simulation framework,validated against laboratory experiments,systematically evaluates the influence of grouser geometry(involute,triangular,and pin-type)and traveling speed(0.2–1.0 m/s)on traction performance,slip rate,and ground pressure distribution.Results reveal rate-dependent traction mechanisms governed by soil microstructural responses:higher speeds enhance peak traction but exacerbate slip instability on complex terrain.Critical operational thresholds are established—0.7 m/s for flat terrain,≤0.5 m/s for slopes and ditches—with distinct grouser optimization strategies:involute grousers achieve 35%–40%slip reduction on slopes through progressive soil engagement,while triangular grousers provide optimal impact resistance during ditch crossing with 30%–35%performance improvement.These findings provide quantitative design criteria and operational guidelines for optimizing TMV structural parameters and control strategies,offering a robust theoretical foundation for enhancing the performance,safety,and reliability of deep-sea mining equipment in complex submarine environments.
基金Project(2012BAB13B03)supported by the National Scientific and Technical Supporting Programs Funded of ChinaProject(41104011)supported by the National Natural Science Foundation of China+1 种基金Project(2013QNB07)supported by the Natural Science Funds for Young Scholar of China University of Mining and TechnologyProject(2012LWB32)supported by the Fundamental Research Funds for the Central Universities,China
文摘Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection guideline of this method was also described. While comparing the parameters of caving mining with equivalent height, the subsidence efficient can be calculated according to the mining height and bulk factor of sagging zone and fracture zone, the tangent of main influence angle of solid backfilling mining is reduced by 0.2-0.5（while it cannot be less than 1.0）. For sake of safety, offset of the inflection point is set to zero, and other parameters, such as horizontal movement coefficient and main propagation angle are equal to the corresponding parameters of caving mining with equivalent height. In the last part, a case study of solid backfilling mining subsidence prediction was described. The results show the applicability of this method and the difference of the maximum subsidence point between the prediction and the observation is less than 5%.
基金Projects (50934006, 51074178) supported by the National Natural Science Foundation of ChinaProject (2010QZZD001) supported by the Fundamental Research Funds for the Central Universities of China
文摘Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps
文摘Shear strain energy is a pivotal physical quantity in the occurrence of earthquakes and rockbursts during deep mining operations.This research is focused on understanding the changes in shear strain energy in the context of retreating longwall mining,which is essential for the optimized design and mitigation of rockbursts and seismic events.Through the application of innovative analytical models,this study expands its analytical range to include the variations in shear strain energy caused by fault coseismic slip.An integrated methodology is utilized,taking into account the changes in coseismic and fault friction parameters as well as enhancements in mining-induced stress and existing background stresses.Our numerical investigation highlights the significance of mining location and fault characteristics as key determinants of shear strain energy modifications.The analysis demonstrates significant spatial variability in shear strain energy,especially noting that fault slip near the mining face greatly increases the likelihood of rockburst.This finding emphasizes the need to integrate fault coseismic slip dynamics into the triggering factors of rock(coal)bursts,thus broadening the theoretical foundation for addressing geological hazards in deep mining operations.The results are further corroborated by observational data from the vicinity of the F16 fault zone,introducing the concept of mining-induced fault coseismic slip as an essential element in the theoretical framework for understanding rockburst triggers.
基金Supported by National Natural Science Foundation of ChinaShanxi Coalbased Low-Carbon Joint Fund(Grant No.U1910211)。
文摘Using electric motors instead of diesel engines as the driving system for mining excavators can reduce the energy consumption and operating costs.However,pure electric-driven mining excavators are prone to unexpected power outages in mines because of drastic changes in load power,leading to significant fluctuations in the power demand of the grid,which in turn affects production.To solve the above problem,a pure electric-driven mining hydraulic excavator based on electric-motor-driven swing platform and hydraulic pumps was used as the research object.Moreover,supercapacitors and DC/DC converter,as the energy storage system(ESS)adjust the output power of the grid and recover the braking kinetic energy of the swing platform.Subsequently,a novel integrated energy management strategy for a DC bus voltage predictive controller based on the power feedforward of fuzzy rules is proposed to run mining excavators efficiently and reliably.Specifically,the working modes of the ESS are determined by the DC bus voltage and state of charge(SOC)of the supercapacitor.Next,the output power of the supercapacitor and the DC bus voltage were controlled by adjusting the charging and discharging currents of the DC/DC converter using a predictive controller and fuzzy rules.In addition,a digital prototype of the excavator was verified using an original machine test.The performance of the different strategies and driven systems were analyzed using digital prototypes.The results showed that,compared with traditional excavators with diesel engines,the operational cost of the developed excavators was reduced by 54.02%.Compared to pure electric-driven excavators without an ESS,the peak power of the grid for the developed excavators was reduced by 10%.This study designed an integrated energy management strategy for a pure electric mining excavator that can regulate the power output of the grid and maintain the stability of the bus voltage and SOC of the ESS.
基金supported by the National Natural Science Foundation of China(Nos.42177124 and 41877277)Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(No.SKLGME022011)+2 种基金Fundamental Research Funds for the Central Universities(No.2024KYJD1011)Frontier Technologies R&D Program of Jiangsu(No.BF2024056)the Graduate Innovation Program of China University of Mining and Technology(No.KYCX25_3085)。
文摘Salt deposits in China predominantly originate from lake deposits,characterized by thin salt beds interspersed with numerous interlayers,collectively termed bedded salt formations.Historically,the solution mining practices have adopted the layered solution mining approach,inspired by coal mining techniques.However,this approach fails to account for the unique challenges of salt solution mining.Practical implementation is inefficient,costs escalate post-construction,and cavern geometry is constrained by salt beds thickness.Additionally,resource loss in abandoned beds and stability risks in adjacent mining zones remain unresolved.This study investigates mining scheme selection for low-grade salt deposits in Huai'an Salt Basin,introducing a continuous solution mining method that traverses multiple interlayers.Through comprehensive analysis of plastic deformation in caverns and surrounding rock,volume shrinkage rates,and economic costs comparing continuous and layered solution mining approaches,the results demonstrate that:(1)In the layered solution mining with horizontal interconnected wells scheme,plastic deformation zones propagate unevenly,posing interlayer connectivity risks.Concurrently,roof subsidence and floor heave destabilize the structure;(2)the continuous solution mining with horizontal interconnected wells scheme reduces plastic deformation zones to 3.4%of cavern volume,with volumetric shrinkage below 17%,markedly improving stability;(3)Economically,the continuous solution mining scheme generates caverns 2.43 times larger than the layered solution mining,slashing unit volume costs to 41.1%while enhancing resource recovery and long-term viability.The continuous method demonstrates distinct economic advantages and achieves higher resource utilization efficiency in solution mining compared to layered mining.Furthermore,its superior cavern stability presents strong potential for large-scale implementation.
基金financially supported by the Fundation of Key Laboratory of Ministry of Natural Resources for Eco-geochemistry (ZSDHJJ202202)Geological Investigation and Evaluation of Shale Gas in Complex Structural Areas of the Middle Yangtze plate(DD20250200604) of China Geological Survey+1 种基金the Natural Science Foundation of Guangdong Province,China(2023A1515140061)the Dongguan Science and Technology of Social Development Program(20231800935842, 20231800940562).
文摘To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and Ni in China’s Dexing copper mining district through paired sampling of water-amphibians,soil-earthworms,and air-lichens.Advanced methodologies were employed,including ICP-MS quantification for heavy metals,geochemical indices(Igeo,BCF,BAF)to assess bioavailability,NMDS for source apportionment,and HPLC to detect DNA methylation alterations.Aquatic systems exhibited severe Cd/Pb enrichment(16.25-24.42μg/L;11-15×WHO limits),while agricultural soils showed extreme Cd contamination(1.5 mg/kg;15×background).Biota displayed metal-specific accumulation:frogs achieved BCFs>1,000 for Pb/Cd,earthworms showed pH-modulated BAFs>2.5 for Cd/As,and lichens recorded 100-1,000×atmospheric Cr enrichment.NMDS resolved three contamination pathways:mining-derived Cd/Pb/As(MDS1=2.56),atmospheric Cr(PC2=1.84),and geogenic Ni.Cd dominated ecological risks(Eri=554.25;RI 300),while atmospheric Cr drove carcinogenic risks(TCR=4.11×10^(-5))exceeding safety thresholds.The source-media-biota-risk framework pioneers the integration of geochemical transport with epigenetic toxicity biomarkers,demonstrating that sub-lethal Cd/Pb exposure induces genome-wide DNA hypomethylation(2.4%-6.6%reduction;ρ=−0.71 to−0.91).This paradigm shift prioritizes bioavailability-informed regulations over concentration-based metrics,offering actionable strategies for sustainable development goals-aligned mining pollution control.
基金supported by the National Natural Science Foundation of China (No. 51404278)the State Key Program of National Natural Science Foundation of China (No. 51134005)
文摘With the third innovation in science and technology worldwide, China has also experienced thismarvelous progress. Concerning the longwall mining in China, the ＂masonry beam theory＂ （MBT） wasfirst proposed in the 1960s, illustrating that the transmission and equilibrium method of overburdenpressure using reserved coal pillar in mined-out areas can be realized. This forms the so-called ＂121mining method＂, which lays a solid foundation for development of mining science and technology inChina. The ＂transfer rock beam theory＂ （TRBT） proposed in the 1980s gives a further understanding forthe transmission path of stope overburden pressure and pressure distribution in high-stress areas. In thisregard, the advanced 121 mining method was proposed with smaller coal pillar for excavation design,making significant contributions to improvement of the coal recovery rate in that era. In the 21st century,the traditional mining technologies faced great challenges and, under the theoretical developmentspioneered by Profs. Minggao Qian and Zhenqi Song, the ＂cutting cantilever beam theory＂ （CCBT） wasproposed in 2008. After that the 110 mining method is formulated subsequently, namely one stope face,after the first mining cycle, needs one advanced gateway excavation, while the other one is automaticallyformed during the last mining cycle without coal pillars left in the mining area. This method can beimplemented using the CCBT by incorporating the key technologies, including the directional presplittingroof cutting, constant resistance and large deformation （CRLD） bolt/anchor supporting systemwith negative Poisson＇s ratio （NPR） effect material, and remote real-time monitoring technology. TheCCBT and 110 mining method will provide the theoretical and technical basis for the development ofmining industry in China.
基金financially supported by the State Key Research Development Program of China(Grant No.2016YFC0600701)the National Natural Science Foundation of China(Grant No.51674170)
文摘In this study, the spatial distributions of stress and fracture fields for three typical underground coal mining layouts, Le, non-pillar mining （NM）, top-coal caving mining （TCM） and protective coal-seam mining （PCM）, are modeled using discrete element software UDEC, The numerical results show that different mining layouts can lead to different mining-induced stress fields, resulting in diverse fracture fields, For the PCM, the mining influenced area in front of the mining faces is the largest, and the stress concentration factor in front of the mining faces is the lowest, The spatial shapes of the mining-induced fracture fields under NM, TCM and PCM differ, and they are characterized by trapezoidal, triangular and tower shapes, respectively, The fractal dimensions of mining-induced fractures of the three mining layouts decrease in the order of PCM, TCM and NM, It is also shown that the PCM can result in a better gas control effect in coal mines with high outburst potential, The numerical results are expected to provide a basis for understanding of mining-induced gas seepage fields and provide a reference for high- efficiency coal mining,
基金supported by the National Natural Science Foun dation of China(52374170 and 51974313)the National Key Research and Development Plan Project(2022YFF1303300).
文摘1.Introduction Changes in land use are key factors promoting global climate change,and the side effects of mining activity that destroy the soil,vegetation,and biodiversity lead to imbalanced carbon cycling in terrestrial ecosystems.
文摘The rehabilitation of coal mines is an up-to-date issue, heavily discussed not only by the industry but also by scientists and the adjacent communities since open cut coal mining has extensive impacts affecting all parties. Whereas, before and during the mining process not only nature but sometimes also the population of a whole region has to give way to a mine, the consequences of the operations remain long after mining closure. Typically a once intact and functioning ecosystem is replaced with a destroyed wideness evocative of a moon landscape. Fortunately, the awareness of the need to rehabilitate the destroyed nature is increasing steadily and all involved parties are making efforts to improve the situation, even if it is a major challenge to bring all parties to a consensus. Therefore, a legislative basis is required and the know-how of optimal rehabilitation solutions must be developed. In this article the rehabilitation of mined land in Australia and Germany are compared. More precisely the article will present an overview of the legislative regulations, certain applied methods of rehabilitation work and the problems that are likely to occur in respect to the influence of mining on nature.
基金supported by Technology Innovation Fund of China Coal Research Institute(2022CX-I-04)Science and Technology Innovation Venture Capital Project of China Coal Technology Engineering Group(2020-2-TD-CXY005)。
文摘Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.
基金funded by Guizhou Provincial Science and Technology Project,Qiankehejichu-ZK[2022]-YB529Guizhou Education Department(Youth Science and Technology Topnotch Talent Project)QJJ[2024]345+1 种基金Guizhou Provincial Science and Technology Project,QKHJC-ZK[2023]-YBGuizhou Education Department Youth Science and Technology Talents Growth Project,QJHKY[2020]122.
文摘The complex and diverse nature of coal mining sites,including different landforms and working conditions,presents challenges for rehabilitation efforts.To address this,we conducted a comprehensive experimental study focusing on microbially induced calcium carbonate precipitation(MICP)remediation,considering the fracture characteristics of coal mining sites.The MICP-restored samples were subjected to confined/unconfined compressive strength,uniaxial/triaxial permeability,and souring tests to assess their restoration efficacy.The results showed that under similar mining conditions,the average depth of parallel fractures was 0.185 m for loess ridges,0.16 m for the valley,and 0.146 m for the blown-sand region,while the average depth for boundary fractures was 0.411 m for loess ridges,0.178 m for the valley,and 0.268 m for the blown-sand region.Notably,parallel fractures showed negligible filling in all landforms,whereas boundary fractures in the blown-sand region were completely filled with wind-deposited sand.The valley landform was filled with alluvium and wind-deposited sand,whereas the loess landform was filled with wind-deposited sand and loess.MICP-restored soil samples in all landforms achieved a strength comparable to remolded fracture-free soil samples.Across all landforms,the maximum permeability coefficient of MICP-restored soil samples closely matched that of remolded fracture-free soil samples.Under similar topographic and rainfall conditions MICP restorations scoured 31.3 g on blown-sand region,19.3 g on loess ridges,and 17.6 g on valleys.These research findings provide an experimental foundation for MICP repair of coal mining ground fractures.
基金supported by the National Natural Science Foundation of China(Nos.12172248,12302022,12021002,and 12132010)the Tianjin Research Program of Application Foundation and Advanced Technology of China(No.23JCZDJC00950)。
文摘Belt conveyors are extensively utilized in mining and power industries.In a typical coal mine conveyor system,coal is transported over distances exceeding 2 km,involving more than 20000 idlers,which far exceeds a reasonable manual inspection capacity.Given that idlers typically have a lifespan of 1-2 years,there is an urgent need for a rapid,cost-effective,and intelligent safety monitoring system.However,current embedded systems face prohibitive replacement costs,while conventional monitoring technologies suffer from inefficiency at low rotational speeds and lack systematic structural optimization frameworks for diverse idler types and parameters.To address these challenges,this paper introduces an integrated,on-site detachable self-powered idler condition monitoring system(ICMS).This system combines energy harvesting based on the magnetic modulation technology with wireless condition monitoring capabilities.Specifically,it develops a data-driven model integrating convolutional neural networks(CNNs) with genetic algorithms(GAs).The conventional testing results show that the data-driven model not only significantly accelerates the parameter response time,but also achieves a prediction accuracy of 92.95%.The in-situ experiments conducted in coal mines demonstrate the system's reliability and monitoring functionality under both no-load and fullload conditions.This research provides an innovative self-powered condition monitoring solution and develops an efficient data-driven model,offering feasible online monitoring approaches for smart mine construction.
基金financially supported by the National Key Research and Development Program of China(Grant No.2023YFC2811600)the National Natural Science Foundation of China(Grant Nos.52301349 and 52088102)+1 种基金the Qingdao Post-Doctorate Science Fund(No.QDBSH20220202070)the Major Scientific and Technological Innovation Project of Shandong Province(Grant No.2019JZZY010820).
文摘A deep-sea mining riser is a crucial component of the system used to lift seafloor mineral resources to the vessel.It is prone to damage and failure because of harsh environmental conditions and internal fluid erosion.Furthermore,damage can impact the response characteristics of the riser,but varying environmental loadings easily mask it.Thus,distin-guishing between riser damage and environmental effects poses a considerable challenge.To address this issue,a cantilevered model is created for a deep-sea mining riser via the concentrated mass method,and a time-domain analytical strategy is developed.The vortex-induced vibration(VIV)response characteristics of the riser are initially examined,considering various damage conditions and flow velocities.The study results revealed four primary observations:(a)effective tension can serve as a reliable indicator for identifying damage at lower velocities;(b)there are noticeable differences in displacement between the healthy and damaged risers in the in-line direction rather than the cross-flow direction;(c)frequency characteristics can more effectively distinguish the damage conditions at high flow velocities,with the mean square frequency and frequency variance being more effective than the centroid frequency and root variance frequency;(d)displacement differences are more sensitive to damage occurring near the top and bottom of the riser,while both velocity variations and structural damage can influence displacements,especially in regions between modal nodes.The vibrational behavior and damage indicators are clarified for structural health monitoring of deep-sea mining risers during lifting operations.
